1. Field of the Invention
The present invention relates to improved fasteners that utilize swaged-on collars.
2. Description of the Prior Art
A type of prior art fastener widely utilized in the aerospace industry typically comprises head, shank and pin tail portions, the shank portion extending through aligned apertures formed in adjacent panels, the shank portion typically having a single gripping ledge formed thereon. A collar is swaged onto the shank portion in a manner such that the collar is secured by the gripping ledge in place against a surface of one of the panels.
Occasions arise wherein it is desired to remove the fastener described above from its installation. This in turn requires that the swaged-on collar be machined off using a special tool. The possibility exists that the single gripping ledge will be damaged during collar removal, thus preventing the fastener from being reused. In addition, the removal process is relatively time consuming, increasing the costs associated with the process. Finally, the conventional arrangement forces the collar tightly against the panel surface. Certain applications, on the other hand, dictate that the collar be positioned loosely against the panel surface.
What is therefore desired is to provide a fastener system of the type described hereinabove wherein the swaged-on collar can be removed without damaging the shank portion and wherein removal could be accomplished relatively quickly.